Mast "pumping" (not under sail, at the dock).. ? - SailNet Community
 7Likes
Reply
 
LinkBack Thread Tools
post #1 of 13 Old 03-29-2012 Thread Starter
Sailors do like Heineken!
 
chrisncate's Avatar
 
Join Date: Jan 2010
Location: Maryland
Posts: 4,574
Thanks: 18
Thanked 34 Times in 34 Posts
Rep Power: 6
 
Mast "pumping" (not under sail, at the dock).. ?

...

Last edited by chrisncate; 03-03-2015 at 01:36 AM.
chrisncate is offline  
Quote Quick Reply Share with Facebook
Sponsored Links
Advertisement
 
post #2 of 13 Old 03-29-2012
Senior Member
 
Captainmeme's Avatar
 
Join Date: Aug 2008
Location: East Tennessee
Posts: 1,043
Thanks: 8
Thanked 29 Times in 28 Posts
Rep Power: 8
 
Re: Mast "pumping" (not under sail, at the dock).. ?

I've always wondered about this term "mast pumping". To me it conveys the action of vertical displacement. Yes, that the mast moves up then down. Is that what your mast is doing? Moving up and down? Not side to side or forward and backwards?
Captainmeme is offline  
Quote Quick Reply Share with Facebook
post #3 of 13 Old 03-29-2012
Just another Moderator
 
Faster's Avatar
 
Join Date: Sep 2005
Location: New Westminster, BC
Posts: 16,577
Thanks: 110
Thanked 321 Times in 306 Posts
Rep Power: 10
     
Re: Mast "pumping" (not under sail, at the dock).. ?

Some rigs do tend to 'pump' in certain breezes, it can vary with wind strength and wind angle. For example on a previous boat even properly tuned, 20 knots across the beam at the dock resulted in some pumping. It was rarely an issue because we generally wouldn't be on board overnight in those conditions. It never really happened on the hook unless it was really blustery.

You could try tuning the lowers to try to minimize it, esp if you put a little prebend (forward lowers pulling the mast forward slightly) or perhaps just up the tension a bit to see if it helps.

OTOH when that occurs it's kind of like a built-in anchor watch alarm.. go to sleep in calm conditions, the noise will wake you up to have a look around..
baloccad likes this.

Ron

1984 Fast/Nicholson 345 "FastForward"

".. there is much you could do at sea with common sense.. and very little you could do without it.."
Capt G E Ericson (from "The Cruel Sea" by Nicholas Monsarrat)
Faster is offline  
Quote Quick Reply Share with Facebook
post #4 of 13 Old 03-29-2012
Senior Member
 
casey1999's Avatar
 
Join Date: Oct 2010
Location: HI
Posts: 3,325
Thanks: 21
Thanked 46 Times in 45 Posts
Rep Power: 5
 
Re: Mast "pumping" (not under sail, at the dock).. ?

Chris,
Here is a good tuning guide:
selden mast tuning guide - Bing

I also need to replace my standing rigging in the next couple years. How do you plan to change out your forestay, backstay and upper shrouds? Will you rig a temp halyard while you do the work to support? I am a little nervous to be at the top of mast with only a halyard holding her up. Boat looks great.
casey1999 is offline  
Quote Quick Reply Share with Facebook
post #5 of 13 Old 03-29-2012
Chastened
 
BubbleheadMd's Avatar
 
Join Date: Nov 2009
Location: Edgewater/Annapolis
Posts: 3,396
Thanks: 2
Thanked 82 Times in 77 Posts
Rep Power: 6
 
Send a message via Yahoo to BubbleheadMd
Re: Mast "pumping" (not under sail, at the dock).. ?

CnC-

I just dealt with this issue on my boat, (discussed on another forum). You and I both have "telephone pole" rigs. Thick masts that are only made to have a tiny amount of pre-bend.

Snug up your forward lowers 1/2 turn each. Maybe 1 turn. If the aft lowers get tight when you do this, then loosen them a corresponding amount of turns.

Also, take your jib halyard over to a stbd stanchion base (just pick one) and mark exactly where it reaches the toe rail with a piece of tape. Take the halyard over to the same stanchion base on the port side. The halyard should reach the toe rail at the taped mark on the halyard. If it doesn't, then your mast is canted in one direction or the other, and you need to loosen everything and start over.

Get the mast centered directly over the boat.
chrisncate likes this.

S/V Old Shoes
1973 Pearson 30 #255
BubbleheadMd is offline  
Quote Quick Reply Share with Facebook
post #6 of 13 Old 03-29-2012
Superior Sailor
 
Squidd's Avatar
 
Join Date: Sep 2011
Location: Eagle River Wi.
Posts: 978
Thanks: 6
Thanked 9 Times in 8 Posts
Rep Power: 4
 
Re: Mast "pumping" (not under sail, at the dock).. ?

Quote:
Also, take your jib halyard over to a stbd stanchion base (just pick one) and mark exactly where it reaches the toe rail with a piece of tape. Take the halyard over to the same stanchion base on the port side. The halyard should reach the toe rail at the taped mark on the halyard. If it doesn't, then your mast is canted in one direction or the other, and you need to loosen everything and start over.
Thats assuming your halyard sheaves are centered at the top of the mast...won't work if they are side by side...

"Might as well take 'er out...If anything is gonna happen...It's gonna happen out there..."
"Captin Ron"
Squidd is offline  
Quote Quick Reply Share with Facebook
post #7 of 13 Old 03-29-2012
Member
 
JimMcGee's Avatar
 
Join Date: Jun 2005
Location: Barnegat Bay, NJ
Posts: 1,816
Thanks: 62
Thanked 51 Times in 48 Posts
Rep Power: 11
 
Re: Mast "pumping" (not under sail, at the dock).. ?

Chris,
I get the same thing at the dock when the wind is piping up on the beam. Tuning the rig helped quite a bit, and for my rig the standard tune calls for a bit of additional tension on the foward lowers as Bubblehead suggested. But this didn't eliminate the problem completely.

I found posts on some forums that suggested taking a couple of wraps around the mast with your main halyard to break up the wind currents. That didn't help with my boat (though it might with yours).

A Loos gauge isn't terribly expensive, I think around $60 at Defender, and makes tuning the rig easy. The cheaper solution is a big box of foam earplugs -- $15 from Lowes.

Don't laugh my wife always wears them when sleeping aboard.

You get used to the sounds your boat makes and you register a lot of information about her without realizing it just by how she sounds and feels.

The noise that woke me bolt upright out of a sound sleep was the sound of claws dragging across the deck right over my head in the v-berth.

Turned out it was a heron!
chrisncate likes this.

95 Catalina 30 Island Time

The sail, the play of its pulse so like our own lives: so thin and yet so full of life, so noiseless when it labors hardest, so noisy and impatient when least effective." - Henry David Thoreau
JimMcGee is offline  
Quote Quick Reply Share with Facebook
post #8 of 13 Old 03-29-2012
Member
 
JimMcGee's Avatar
 
Join Date: Jun 2005
Location: Barnegat Bay, NJ
Posts: 1,816
Thanks: 62
Thanked 51 Times in 48 Posts
Rep Power: 11
 
Re: Mast "pumping" (not under sail, at the dock).. ?

You may have already covered this in another post.

How are your cruising plans coming? You must be pretty close to casting off?

95 Catalina 30 Island Time

The sail, the play of its pulse so like our own lives: so thin and yet so full of life, so noiseless when it labors hardest, so noisy and impatient when least effective." - Henry David Thoreau
JimMcGee is offline  
Quote Quick Reply Share with Facebook
post #9 of 13 Old 03-29-2012
Senior Member
 
Join Date: Jan 2012
Location: British Columbia
Posts: 2,664
Thanks: 20
Thanked 40 Times in 38 Posts
Rep Power: 4
 
Re: Mast "pumping" (not under sail, at the dock).. ?

Running back stays, from the spreaders to a point well aft ,eliminate the problem.

Brent Swain, Boat designer, Builder, and author of "Origami Metal Boatbuilding"
Brent Swain is offline  
Quote Quick Reply Share with Facebook
post #10 of 13 Old 03-29-2012 Thread Starter
Sailors do like Heineken!
 
chrisncate's Avatar
 
Join Date: Jan 2010
Location: Maryland
Posts: 4,574
Thanks: 18
Thanked 34 Times in 34 Posts
Rep Power: 6
 
Re: Mast "pumping" (not under sail, at the dock).. ?

Quote:
Originally Posted by BubbleheadMd View Post
CnC-

I just dealt with this issue on my boat, (discussed on another forum). You and I both have "telephone pole" rigs. Thick masts that are only made to have a tiny amount of pre-bend.

Snug up your forward lowers 1/2 turn each. Maybe 1 turn. If the aft lowers get tight when you do this, then loosen them a corresponding amount of turns.

Also, take your jib halyard over to a stbd stanchion base (just pick one) and mark exactly where it reaches the toe rail with a piece of tape. Take the halyard over to the same stanchion base on the port side. The halyard should reach the toe rail at the taped mark on the halyard. If it doesn't, then your mast is canted in one direction or the other, and you need to loosen everything and start over.

Get the mast centered directly over the boat.
I did (my halyards are centered), and I think I resolved it mostly. I think once I replace my crappy old rigging the rest of it will go away for the most part. Thanks!

I am still left wondering if my rigging is too tight though..
chrisncate is offline  
Quote Quick Reply Share with Facebook
Reply

Quick Reply
Message:
Options

By choosing to post the reply above you agree to the rules you agreed to when joining Sailnet.
Click Here to view those rules.

Register Now



In order to be able to post messages on the SailNet Community forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
Please note: After entering 3 characters a list of Usernames already in use will appear and the list will disappear once a valid Username is entered.


User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in









Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Similar Threads
Thread Thread Starter Forum Replies Last Post
Any reviews of Don Guillette's "Sail Trim Chart" or "Sail Trim User's Guide"? 0verdrive Learning to Sail 6 02-07-2015 01:17 PM
"Seacock" vs. "ballcock" or "ball valve?" SEMIJim Gear & Maintenance 18 09-02-2013 05:31 PM
Need some dock "Neighbor" advice KeelHaulin General Discussion (sailing related) 73 04-27-2009 10:59 PM
C270 Main Sail "stack Pack", Quick Cover", "lazy Bag" Install randy22556 Catalina 1 02-28-2007 11:53 AM
C-270 Main Sail zippered cover w/ lazy jacks, "Lazy Bag", "Quick Cover" Installation randy22556 Gear & Maintenance 0 02-27-2007 05:02 PM

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome